Private pilot speaking...
In the US, the terminology will be:
"Cleared to Reynolds Airport; David Two RNAV Departure, Kingham Transition; then, as filed. Maintain niner thousand. Expect flight level four one zero, one zero minutes after departure."
http://www.faa.gov/airports_airtraff...atc0403.html.1
You will find that most often, the transition fix will be a point on the airway you will be joining.
In other countries, the clearance is usually delivered as:
"Cleared to Milian via the AR1..."
Like you, I've never heard the "as filed", but would assume that it is implied since you presumably have filed the AR1 as your first airway. I'm sure if you check the ICAO documents it will say that you may proceed as filed.